Furuno CSH-84, CSH-83 manual Control Function

Control	Function
NORM, E/S, HIST	Select display mode: NORM, normal sonar picture; E/S, Echo sounder
(Mode keys)	combination; HIST, Historical display.
	Lamp above a key lights to show current selection.
RECALL, MEMO	RECALL: Replays saved picture.
	MEMO: Saves picture to memory card or internal memory.
RANGE	Selects a picture display range. Range selected appears on the display.
GAIN	Adjusts receiver sensitivity.
TARGET SLICE	Using automatic tilting, displays the echo inside the estimate mark at
	several different tilt angles.
VERT SCAN	Not used.
SHOOT	Press when net is cast. The net shooting mark, *net sonde marks and
	*current mark appear at the own ship mark. The net shooting mark,
	net sonde marks and current mark move on the *ship's track as the
	ship moves. The lamp above the switch lights and time *distance run
	appears on the display until the net shooting mark is turned off.
	(* Requires external sensor.)
R/B	Provides range and bearing data from own ship to a target. Select
	target with trackball and then press the R/B key. A line connects
	between own ship mark and trackball mark to show bearing to target.
TILT	Changes the tilt angle of the sounding beam between -5°and 60°.
AUTO TILT	Automatically tilts the sounding beam up and down in 1° or 2° steps
	within the tilt angle selected by the WIDTH key. The lamp above the
	key lights when automatic tilt is on.
WIDTH	Sets tilt width in automatic tilt.
NET COURSE	Marks location of net.
TARGET LOCK	Tracks a fish school.
EVENT	Inscribe event mark on the display, to find horizontal, range, depth
	and bearing to a target. Event key can be functioned as SHOOT
	key of remote control box.
ESTIMATE 1, 2	Compare volume of two fish schools.
FISH	Measures fish school speed.
OFF-CENT	Relocates selected target.
DIM	Adjusts the backlighting of the control panels and the brightness of
	the lamps above keys.
CONT	Adjusts screen contrast.
BRILL	Adjusts screen brilliance.
AUDIO	Adjusts volume of built-in loudspeaker, which monitors a target
	appearing along the bearing marker.
TRACKBALL	Follows on-screen movement of the trackball mark, to enter marks
	and off-center the screen.

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